User Operations in .Net

• To get name of user HttpContext.Current.User.Identity.Name

About LDAP

First instantiate a DirectoryEntry object pointing it to the directory path to search. Next instantiate a DirectorySearcher object and pass along the DirectoryEntry object, telling it this is the directory path to search in. The DirectorySearcher.SearchScope property sets the search scope and has three different values – Base, OneLevel and SubTree. Base searches only the directory path you bound to. OneLevel searches the immediate children of the directory path bound to. And SubTree searches all descendants of the directory path bound to. The code sample sets it to OneLevel to search only the immediate children of the directory path bound to. The DirectorySearcher.Filter property sets the filter to apply for the search. You can filter on any property the directory object has and also use wildcards. The syntax used is property name equals value surrounded with parenthesis, for example "(cn=Klaus)". If you filter on more then one property then you need to specify the logical "&" or "" operator. First you specify the logical operator followed by the list of property/name filters and the whole filter is again surrounded with parenthesis, for example "(&(cn=Klaus)(objectClass=user))" or "((cn=Klaus)(cn=Peter))". The first example finds any object with the name Klaus and of the type user. The second example finds any object with the name Klaus or Peter. You can use the greater, greater equal, equal, less and less then operators (>, >=, =, <, <=). Any combination is possible, for example "(&(objectClass=classSchema)((cn=organizational-unit)(cn=organization)))" searches for all object types with the name organizational-unit or organization.

After setting the search scope and filter you call FindAll() to find all matching directory objects. This returns a SearchResultColletion which you can loop through and for each found directory object you get a SearchResult object. The SearchResult.Path property returns the path of the found directory object. You can also get an instance of the found directory object via SearchResult.GetDirectoryEntry(). In our code sample we add each found directory object to the tree view and call FillTreeView() to add any descendants of the directory object to the tree view. Don't forget to call Close() for every directory object we get by calling SearchResult.GetDirectoryEntry(). When done looping through the SearchResultCollection call Dispose() to free up the search result collection. At the end we call Dispose() on the DirectorySearcher object and Close() on the DirectoryEntry object used to bind to the directory path we wanted to search.

The DirectoryEntry.Properties property gives you access to all properties of a directory object. It returns a PropertyCollection, the collection of properties for this directory object. PropertyCollection.PropertyNames returns a collection of all property names and PropertyCollection[PropertyName] gives you access to the value of this property. A property value can be single valued or it can be an array of object values. So you can loop through all property values.